1/*
2 * untgz.c -- Display contents and extract files from a gzip'd TAR file
3 *
4 * written by Pedro A. Aranda Gutierrez <paag@tid.es>
5 * adaptation to Unix by Jean-loup Gailly <jloup@gzip.org>
6 * various fixes by Cosmin Truta <cosmint@cs.ubbcluj.ro>
7 */
8
9#include <stdio.h>
10#include <stdlib.h>
11#include <string.h>
12#include <time.h>
13#include <errno.h>
14
15#include "zlib.h"
16
17#ifdef unix
18#  include <unistd.h>
19#else
20#  include <direct.h>
21#  include <io.h>
22#endif
23
24#ifdef WIN32
25#include <windows.h>
26#  ifndef F_OK
27#    define F_OK  0
28#  endif
29#  define mkdir(dirname,mode)   _mkdir(dirname)
30#  ifdef _MSC_VER
31#    define access(path,mode)   _access(path,mode)
32#    define chmod(path,mode)    _chmod(path,mode)
33#    define strdup(str)         _strdup(str)
34#  endif
35#else
36#  include <utime.h>
37#endif
38
39
40/* values used in typeflag field */
41
42#define REGTYPE  '0'            /* regular file */
43#define AREGTYPE '\0'           /* regular file */
44#define LNKTYPE  '1'            /* link */
45#define SYMTYPE  '2'            /* reserved */
46#define CHRTYPE  '3'            /* character special */
47#define BLKTYPE  '4'            /* block special */
48#define DIRTYPE  '5'            /* directory */
49#define FIFOTYPE '6'            /* FIFO special */
50#define CONTTYPE '7'            /* reserved */
51
52/* GNU tar extensions */
53
54#define GNUTYPE_DUMPDIR  'D'    /* file names from dumped directory */
55#define GNUTYPE_LONGLINK 'K'    /* long link name */
56#define GNUTYPE_LONGNAME 'L'    /* long file name */
57#define GNUTYPE_MULTIVOL 'M'    /* continuation of file from another volume */
58#define GNUTYPE_NAMES    'N'    /* file name that does not fit into main hdr */
59#define GNUTYPE_SPARSE   'S'    /* sparse file */
60#define GNUTYPE_VOLHDR   'V'    /* tape/volume header */
61
62
63/* tar header */
64
65#define BLOCKSIZE     512
66#define SHORTNAMESIZE 100
67
68struct tar_header
69{                               /* byte offset */
70  char name[100];               /*   0 */
71  char mode[8];                 /* 100 */
72  char uid[8];                  /* 108 */
73  char gid[8];                  /* 116 */
74  char size[12];                /* 124 */
75  char mtime[12];               /* 136 */
76  char chksum[8];               /* 148 */
77  char typeflag;                /* 156 */
78  char linkname[100];           /* 157 */
79  char magic[6];                /* 257 */
80  char version[2];              /* 263 */
81  char uname[32];               /* 265 */
82  char gname[32];               /* 297 */
83  char devmajor[8];             /* 329 */
84  char devminor[8];             /* 337 */
85  char prefix[155];             /* 345 */
86                                /* 500 */
87};
88
89union tar_buffer
90{
91  char               buffer[BLOCKSIZE];
92  struct tar_header  header;
93};
94
95struct attr_item
96{
97  struct attr_item  *next;
98  char              *fname;
99  int                mode;
100  time_t             time;
101};
102
103enum { TGZ_EXTRACT, TGZ_LIST, TGZ_INVALID };
104
105char *TGZfname          OF((const char *));
106void TGZnotfound        OF((const char *));
107
108int getoct              OF((char *, int));
109char *strtime           OF((time_t *));
110int setfiletime         OF((char *, time_t));
111void push_attr          OF((struct attr_item **, char *, int, time_t));
112void restore_attr       OF((struct attr_item **));
113
114int ExprMatch           OF((char *, char *));
115
116int makedir             OF((char *));
117int matchname           OF((int, int, char **, char *));
118
119void error              OF((const char *));
120int tar                 OF((gzFile, int, int, int, char **));
121
122void help               OF((int));
123int main                OF((int, char **));
124
125char *prog;
126
127const char *TGZsuffix[] = { "\0", ".tar", ".tar.gz", ".taz", ".tgz", NULL };
128
129/* return the file name of the TGZ archive */
130/* or NULL if it does not exist */
131
132char *TGZfname (const char *arcname)
133{
134  static char buffer[1024];
135  int origlen,i;
136
137  strcpy(buffer,arcname);
138  origlen = strlen(buffer);
139
140  for (i=0; TGZsuffix[i]; i++)
141    {
142       strcpy(buffer+origlen,TGZsuffix[i]);
143       if (access(buffer,F_OK) == 0)
144         return buffer;
145    }
146  return NULL;
147}
148
149
150/* error message for the filename */
151
152void TGZnotfound (const char *arcname)
153{
154  int i;
155
156  fprintf(stderr,"%s: Couldn't find ",prog);
157  for (i=0;TGZsuffix[i];i++)
158    fprintf(stderr,(TGZsuffix[i+1]) ? "%s%s, " : "or %s%s\n",
159            arcname,
160            TGZsuffix[i]);
161  exit(1);
162}
163
164
165/* convert octal digits to int */
166/* on error return -1 */
167
168int getoct (char *p,int width)
169{
170  int result = 0;
171  char c;
172
173  while (width--)
174    {
175      c = *p++;
176      if (c == 0)
177        break;
178      if (c == ' ')
179        continue;
180      if (c < '0' || c > '7')
181        return -1;
182      result = result * 8 + (c - '0');
183    }
184  return result;
185}
186
187
188/* convert time_t to string */
189/* use the "YYYY/MM/DD hh:mm:ss" format */
190
191char *strtime (time_t *t)
192{
193  struct tm   *local;
194  static char result[32];
195
196  local = localtime(t);
197  sprintf(result,"%4d/%02d/%02d %02d:%02d:%02d",
198          local->tm_year+1900, local->tm_mon+1, local->tm_mday,
199          local->tm_hour, local->tm_min, local->tm_sec);
200  return result;
201}
202
203
204/* set file time */
205
206int setfiletime (char *fname,time_t ftime)
207{
208#ifdef WIN32
209  static int isWinNT = -1;
210  SYSTEMTIME st;
211  FILETIME locft, modft;
212  struct tm *loctm;
213  HANDLE hFile;
214  int result;
215
216  loctm = localtime(&ftime);
217  if (loctm == NULL)
218    return -1;
219
220  st.wYear         = (WORD)loctm->tm_year + 1900;
221  st.wMonth        = (WORD)loctm->tm_mon + 1;
222  st.wDayOfWeek    = (WORD)loctm->tm_wday;
223  st.wDay          = (WORD)loctm->tm_mday;
224  st.wHour         = (WORD)loctm->tm_hour;
225  st.wMinute       = (WORD)loctm->tm_min;
226  st.wSecond       = (WORD)loctm->tm_sec;
227  st.wMilliseconds = 0;
228  if (!SystemTimeToFileTime(&st, &locft) ||
229      !LocalFileTimeToFileTime(&locft, &modft))
230    return -1;
231
232  if (isWinNT < 0)
233    isWinNT = (GetVersion() < 0x80000000) ? 1 : 0;
234  hFile = CreateFile(fname, GENERIC_WRITE, 0, NULL, OPEN_EXISTING,
235                     (isWinNT ? FILE_FLAG_BACKUP_SEMANTICS : 0),
236                     NULL);
237  if (hFile == INVALID_HANDLE_VALUE)
238    return -1;
239  result = SetFileTime(hFile, NULL, NULL, &modft) ? 0 : -1;
240  CloseHandle(hFile);
241  return result;
242#else
243  struct utimbuf settime;
244
245  settime.actime = settime.modtime = ftime;
246  return utime(fname,&settime);
247#endif
248}
249
250
251/* push file attributes */
252
253void push_attr(struct attr_item **list,char *fname,int mode,time_t time)
254{
255  struct attr_item *item;
256
257  item = (struct attr_item *)malloc(sizeof(struct attr_item));
258  if (item == NULL)
259    error("Out of memory");
260  item->fname = strdup(fname);
261  item->mode  = mode;
262  item->time  = time;
263  item->next  = *list;
264  *list       = item;
265}
266
267
268/* restore file attributes */
269
270void restore_attr(struct attr_item **list)
271{
272  struct attr_item *item, *prev;
273
274  for (item = *list; item != NULL; )
275    {
276      setfiletime(item->fname,item->time);
277      chmod(item->fname,item->mode);
278      prev = item;
279      item = item->next;
280      free(prev);
281    }
282  *list = NULL;
283}
284
285
286/* match regular expression */
287
288#define ISSPECIAL(c) (((c) == '*') || ((c) == '/'))
289
290int ExprMatch (char *string,char *expr)
291{
292  while (1)
293    {
294      if (ISSPECIAL(*expr))
295        {
296          if (*expr == '/')
297            {
298              if (*string != '\\' && *string != '/')
299                return 0;
300              string ++; expr++;
301            }
302          else if (*expr == '*')
303            {
304              if (*expr ++ == 0)
305                return 1;
306              while (*++string != *expr)
307                if (*string == 0)
308                  return 0;
309            }
310        }
311      else
312        {
313          if (*string != *expr)
314            return 0;
315          if (*expr++ == 0)
316            return 1;
317          string++;
318        }
319    }
320}
321
322
323/* recursive mkdir */
324/* abort on ENOENT; ignore other errors like "directory already exists" */
325/* return 1 if OK */
326/*        0 on error */
327
328int makedir (char *newdir)
329{
330  char *buffer = strdup(newdir);
331  char *p;
332  int  len = strlen(buffer);
333
334  if (len <= 0) {
335    free(buffer);
336    return 0;
337  }
338  if (buffer[len-1] == '/') {
339    buffer[len-1] = '\0';
340  }
341  if (mkdir(buffer, 0755) == 0)
342    {
343      free(buffer);
344      return 1;
345    }
346
347  p = buffer+1;
348  while (1)
349    {
350      char hold;
351
352      while(*p && *p != '\\' && *p != '/')
353        p++;
354      hold = *p;
355      *p = 0;
356      if ((mkdir(buffer, 0755) == -1) && (errno == ENOENT))
357        {
358          fprintf(stderr,"%s: Couldn't create directory %s\n",prog,buffer);
359          free(buffer);
360          return 0;
361        }
362      if (hold == 0)
363        break;
364      *p++ = hold;
365    }
366  free(buffer);
367  return 1;
368}
369
370
371int matchname (int arg,int argc,char **argv,char *fname)
372{
373  if (arg == argc)      /* no arguments given (untgz tgzarchive) */
374    return 1;
375
376  while (arg < argc)
377    if (ExprMatch(fname,argv[arg++]))
378      return 1;
379
380  return 0; /* ignore this for the moment being */
381}
382
383
384/* tar file list or extract */
385
386int tar (gzFile in,int action,int arg,int argc,char **argv)
387{
388  union  tar_buffer buffer;
389  int    len;
390  int    err;
391  int    getheader = 1;
392  int    remaining = 0;
393  FILE   *outfile = NULL;
394  char   fname[BLOCKSIZE];
395  int    tarmode;
396  time_t tartime;
397  struct attr_item *attributes = NULL;
398
399  if (action == TGZ_LIST)
400    printf("    date      time     size                       file\n"
401           " ---------- -------- --------- -------------------------------------\n");
402  while (1)
403    {
404      len = gzread(in, &buffer, BLOCKSIZE);
405      if (len < 0)
406        error(gzerror(in, &err));
407      /*
408       * Always expect complete blocks to process
409       * the tar information.
410       */
411      if (len != BLOCKSIZE)
412        {
413          action = TGZ_INVALID; /* force error exit */
414          remaining = 0;        /* force I/O cleanup */
415        }
416
417      /*
418       * If we have to get a tar header
419       */
420      if (getheader >= 1)
421        {
422          /*
423           * if we met the end of the tar
424           * or the end-of-tar block,
425           * we are done
426           */
427          if (len == 0 || buffer.header.name[0] == 0)
428            break;
429
430          tarmode = getoct(buffer.header.mode,8);
431          tartime = (time_t)getoct(buffer.header.mtime,12);
432          if (tarmode == -1 || tartime == (time_t)-1)
433            {
434              buffer.header.name[0] = 0;
435              action = TGZ_INVALID;
436            }
437
438          if (getheader == 1)
439            {
440              strncpy(fname,buffer.header.name,SHORTNAMESIZE);
441              if (fname[SHORTNAMESIZE-1] != 0)
442                  fname[SHORTNAMESIZE] = 0;
443            }
444          else
445            {
446              /*
447               * The file name is longer than SHORTNAMESIZE
448               */
449              if (strncmp(fname,buffer.header.name,SHORTNAMESIZE-1) != 0)
450                  error("bad long name");
451              getheader = 1;
452            }
453
454          /*
455           * Act according to the type flag
456           */
457          switch (buffer.header.typeflag)
458            {
459            case DIRTYPE:
460              if (action == TGZ_LIST)
461                printf(" %s     <dir> %s\n",strtime(&tartime),fname);
462              if (action == TGZ_EXTRACT)
463                {
464                  makedir(fname);
465                  push_attr(&attributes,fname,tarmode,tartime);
466                }
467              break;
468            case REGTYPE:
469            case AREGTYPE:
470              remaining = getoct(buffer.header.size,12);
471              if (remaining == -1)
472                {
473                  action = TGZ_INVALID;
474                  break;
475                }
476              if (action == TGZ_LIST)
477                printf(" %s %9d %s\n",strtime(&tartime),remaining,fname);
478              else if (action == TGZ_EXTRACT)
479                {
480                  if (matchname(arg,argc,argv,fname))
481                    {
482                      outfile = fopen(fname,"wb");
483                      if (outfile == NULL) {
484                        /* try creating directory */
485                        char *p = strrchr(fname, '/');
486                        if (p != NULL) {
487                          *p = '\0';
488                          makedir(fname);
489                          *p = '/';
490                          outfile = fopen(fname,"wb");
491                        }
492                      }
493                      if (outfile != NULL)
494                        printf("Extracting %s\n",fname);
495                      else
496                        fprintf(stderr, "%s: Couldn't create %s",prog,fname);
497                    }
498                  else
499                    outfile = NULL;
500                }
501              getheader = 0;
502              break;
503            case GNUTYPE_LONGLINK:
504            case GNUTYPE_LONGNAME:
505              remaining = getoct(buffer.header.size,12);
506              if (remaining < 0 || remaining >= BLOCKSIZE)
507                {
508                  action = TGZ_INVALID;
509                  break;
510                }
511              len = gzread(in, fname, BLOCKSIZE);
512              if (len < 0)
513                error(gzerror(in, &err));
514              if (fname[BLOCKSIZE-1] != 0 || (int)strlen(fname) > remaining)
515                {
516                  action = TGZ_INVALID;
517                  break;
518                }
519              getheader = 2;
520              break;
521            default:
522              if (action == TGZ_LIST)
523                printf(" %s     <---> %s\n",strtime(&tartime),fname);
524              break;
525            }
526        }
527      else
528        {
529          unsigned int bytes = (remaining > BLOCKSIZE) ? BLOCKSIZE : remaining;
530
531          if (outfile != NULL)
532            {
533              if (fwrite(&buffer,sizeof(char),bytes,outfile) != bytes)
534                {
535                  fprintf(stderr,
536                    "%s: Error writing %s -- skipping\n",prog,fname);
537                  fclose(outfile);
538                  outfile = NULL;
539                  remove(fname);
540                }
541            }
542          remaining -= bytes;
543        }
544
545      if (remaining == 0)
546        {
547          getheader = 1;
548          if (outfile != NULL)
549            {
550              fclose(outfile);
551              outfile = NULL;
552              if (action != TGZ_INVALID)
553                push_attr(&attributes,fname,tarmode,tartime);
554            }
555        }
556
557      /*
558       * Abandon if errors are found
559       */
560      if (action == TGZ_INVALID)
561        {
562          error("broken archive");
563          break;
564        }
565    }
566
567  /*
568   * Restore file modes and time stamps
569   */
570  restore_attr(&attributes);
571
572  if (gzclose(in) != Z_OK)
573    error("failed gzclose");
574
575  return 0;
576}
577
578
579/* ============================================================ */
580
581void help(int exitval)
582{
583  printf("untgz version 0.2.1\n"
584         "  using zlib version %s\n\n",
585         zlibVersion());
586  printf("Usage: untgz file.tgz            extract all files\n"
587         "       untgz file.tgz fname ...  extract selected files\n"
588         "       untgz -l file.tgz         list archive contents\n"
589         "       untgz -h                  display this help\n");
590  exit(exitval);
591}
592
593void error(const char *msg)
594{
595  fprintf(stderr, "%s: %s\n", prog, msg);
596  exit(1);
597}
598
599
600/* ============================================================ */
601
602#if defined(WIN32) && defined(__GNUC__)
603int _CRT_glob = 0;      /* disable argument globbing in MinGW */
604#endif
605
606int main(int argc,char **argv)
607{
608    int         action = TGZ_EXTRACT;
609    int         arg = 1;
610    char        *TGZfile;
611    gzFile      *f;
612
613    prog = strrchr(argv[0],'\\');
614    if (prog == NULL)
615      {
616        prog = strrchr(argv[0],'/');
617        if (prog == NULL)
618          {
619            prog = strrchr(argv[0],':');
620            if (prog == NULL)
621              prog = argv[0];
622            else
623              prog++;
624          }
625        else
626          prog++;
627      }
628    else
629      prog++;
630
631    if (argc == 1)
632      help(0);
633
634    if (strcmp(argv[arg],"-l") == 0)
635      {
636        action = TGZ_LIST;
637        if (argc == ++arg)
638          help(0);
639      }
640    else if (strcmp(argv[arg],"-h") == 0)
641      {
642        help(0);
643      }
644
645    if ((TGZfile = TGZfname(argv[arg])) == NULL)
646      TGZnotfound(argv[arg]);
647
648    ++arg;
649    if ((action == TGZ_LIST) && (arg != argc))
650      help(1);
651
652/*
653 *  Process the TGZ file
654 */
655    switch(action)
656      {
657      case TGZ_LIST:
658      case TGZ_EXTRACT:
659        f = gzopen(TGZfile,"rb");
660        if (f == NULL)
661          {
662            fprintf(stderr,"%s: Couldn't gzopen %s\n",prog,TGZfile);
663            return 1;
664          }
665        exit(tar(f, action, arg, argc, argv));
666      break;
667
668      default:
669        error("Unknown option");
670        exit(1);
671      }
672
673    return 0;
674}
675